/Engine/Plugins/Runtime/MeshModelingToolset/Source/ModelingComponents/Public/BaseTools/SingleSelectionMeshEditingTool.h
Mesh Selection support Set a Selection for the Tool to use. This should be called before toolSetup()(ie in the ToolBuilder) to allow the Tool to configure it's behavior based on the Selection (which may or may-not exist). If the Tool requires a Selection, this needs to be handled at the Builder level.
virtual void SetInputSelection ( const [UDEPRECATED_PersistentMeshSelection](API\Plugins\ModelingComponents\Selection\UDEPRECATED_PersistentMeshSelect-) * SelectionIn )